1. Field of the Invention
The present invention relates to a wired circuit board and an electronic device and, more particularly, to a wired circuit board such as a flexible wired circuit board and an electronic device using the wired circuit board, such as a cellular phone.
2. Description of the Related Art
Conventionally, flexible wired circuit boards have been used in the movable members of various electronic devices such as a cellular phone, a notebook personal computer, and a video camera.
In recent years, in terms of higher data density, an increase in the frequency of a signal has been required in such a flexible wired circuit board. However, when the frequency of the signal is increased, a transmission loss in a signal wiring increases undesirably.
To reduce such a transmission loss, it has been proposed that, e.g., in a wiring board including a line, a shield pattern disposed generally in parallel with the line, a conductor layer (upper conductor layer) disposed to face each of the line and the shield pattern via an insulating layer (upper insulating layer), a conductor layer (lower conductor layer) disposed to face each of the line and the shield pattern via an insulating layer (lower insulating layer), and conductive pillars connecting the upper conductor layer and the lower conductor layer, a ground potential is supplied to each of the shield pattern, the upper conductor layer, the lower conductor layer, and the conductive pillars which surround the line along an extending direction of the line over 360° around the circumference thereof (see, e.g., U.S. Pat. No. 6,353,189).
It has also been proposed that, e.g., in a connector in which a base shield layer, a base insulating layer, a conductor layer composed of a plurality of conductors, a cover insulating layer, and a cover shield layer are successively laminated, the base shield layer and the cover shield layer continuously surround the conductor layer via the base insulating layer and the cover insulating layer (see, e.g., U.S. Pat. No. 4,926,007).